A patent document 1 discloses a technology such that an instantaneous fuel consumption in a short period of time is calculated on a basis of a traveled distance of a vehicle (or a mobile body) and a fuel consumption (economy) determined on a basis of a vehicle speed and this instantaneous fuel consumption is displayed on a display.
Pre-Published Document
Patent Document 1: A Japanese Patent Application First (Laid-open) Publication No. 2011-257429.